The present invention relates to an arrangement for joining a metal member, particularly a rod or a tube, for example a gas connection tube, to a molded body of fireproof or refractory ceramic material, for example, an immersion spout, wherein a metal coupling member for supporting the metal member is arranged or attached to the refractory body.
In a known immersion spout formed of refractory material, a metal coupling is inserted into a bore in the immersion spout for connecting thereto a gas connection tube. The coupling is welded to an annular metal jacket that surrounds the immersion spout, thereby joining the coupling to the immersion spout. This arrangement however has the disadvantage that the annular metal jacket expands to a greater degree than does the refractory material of the immersion spout upon use of the immersion spout at elevated temperatures. Accordingly, the joint between the connection tube and the immersion spout becomes loosened. Another disadvantage of this known arrangement is that the annular metal jacket protrudes or extends outwardly beyond the outer dimension of the immersion spout. The metal jacket thus hinders the extension of the immersion spout through a perforated brick or nozzle brick, for example of a mold. Theoretically, this could be prevented by reducing the wall thickness of the immersion spout by an amount corresponding to the thickness of the metal jacket, or at least by an amount sufficient to enable the immersion spout and metal jacket to extend through a hole of particular diameter of a perforated brick. However, such wall thickness reduction would be undesirable.